The invention concerns panel formwork systems and associated panel formwork arrangements for producing corners and T-shaped intersections of concrete walls by means of a panel formwork.
Panel formwork corner systems are known in the art.
Formworks are used, in particular, for producing concrete walls. The formwork thereby confines a space in which the concrete wall is to be formed. This space is filled with liquid concrete. When the concrete has hardened, the formwork is removed.
Panel formworks enable particularly flexible design of the concrete structures to be erected. A panel formwork is formed by a plurality of individual reusable components that are assembled at the building site in accordance with the respectively desired concrete structure. The most important components of a panel formwork are rectangular panel formwork elements supplemented by panel formwork corner elements. Rectangular panel formwork elements have a relatively low weight, are easy to stack and can be used in any orientation vertically or horizontally.
The individual components of a panel formwork generally comprise a formlining that faces the liquid concrete, and a (generally circumferential) frame runs on the rear side of the component, which mechanically stabilizes the component. Neighboring components are connected by means of turnbuckles, wherein each turnbuckle engages with the frames.
In addition to panel formworks, there are also conventional girder formworks and steel formworks. They may have a mechanically highly robust design but cannot be used with the same flexibility as the panel formworks.
The liquid concrete that is encased between the oppositely disposed formwork elements exerts pressure on the formlinings due to gravity that attempts to force the formwork elements apart. These expansion forces have a maximum value in the lower formwork region. In order to prevent expansion of the formwork, oppositely disposed formwork elements are connected to each other by so-called tie rods. The tie rods penetrate through the formlinings and through the concrete structure to be produced. The tie rods brace the tie plates that abut the rear side of the formwork elements with respect to each other. When the concrete structure is finished, the tie rods and tie plates are removed.
In a conventional panel formwork series, the tie holes through which the tie rods project, extend through the circumferential frame of the rectangular panel formwork elements (so-called edge anchorage). The tie plates are supported on the frame. A tie plate thereby engages behind the frame of the panel formwork element through which the tie rod extends, and also behind the frame of a neighboring panel formwork element. At this neighboring panel formwork element, one tie hole which is disposed below the tie plate is thereby not used, however, there would not be enough space for mounting another tie rod anyway.
Altogether, only part (typically half) of the tie holes are actually used for the tie rods in these conventional panel formwork elements. The remaining part of the tie holes, which would be used for other orientations of the panel formwork elements, must be closed by stoppers when the formwork is erected in order to prevent leakage of liquid concrete.
The arrangement of stoppers requires a considerable amount of work and induces high costs for the production of concrete walls. Falsely arranged stoppers obstruct arrangement of the tie rods and may require correction. Missing stoppers result in leakage of liquid concrete and clogging of tie holes by hardened concrete.
Previous mounting of nut elements for one-sided tie elements for so-called “one-sided anchorage” causes similar problems as false arrangement of stoppers and may also necessitate correction.
One further conventional panel formwork corner system is substantially based on a comparable edge anchorage. This system for forming an oblique-angled obtuse corner of a concrete wall has an inner corner element, an outer corner element, and also two rectangular panel formwork elements that border on the limbs of the inner corner element (inner limbs). The inner corner element is exclusively anchored on the lateral edge of the inner limbs, overlapping the respectively neighboring panel formwork element. The outer corner element has a tie catch in each limb (outer limb), which is utilized for anchoring the inner corner element, and also an edge anchorage that anchors the outer edge of the opposite rectangular panel formwork element.
In this conventional panel formwork corner system, stoppers must be inserted in tie holes that are not used, in particular, in the outer corner element, in the panel formwork elements that belong to the corner system, and in the panel formwork elements that directly border the corner system. False mounting necessitates correction. The same applies for previous mounting of nut elements.
It is therefore the underlying purpose of the present invention to provide a panel formwork corner system that enables erection of a panel formwork with reduced effort, in particular wherein false positioning of stoppers and nuts in and on the tie holes is prevented.